Low-Frequency Noise in AlSb/InAs and Related HEMTs

A comprehensive examination of the low-frequency noise characteristics of AlSb/InAs and related high-electron mobility transistors (HEMTs) in the 6.1-Aring-lattice-constant material system is reported. The effect of gate bias on the noise of devices in this technology is reported for the first time. The slope of the noise level in all the devices examined is nearly 1/f below 100 Hz, but some have significant generation-recombination Lorentzian components at higher frequencies, with an activation energy between 0.30 and 0.40 eV. The Hooge parameter alpha
_H
for open-channel measurements is in the range between 5times10
^-4
and 5times10
^-3
based on measurements at low drain voltage. Comparisons are made to the noise performance of several earlier InAs-based HEMTs with considerably different layer structure and channel composition